self-organization and control in kinetic stimulated raman ... · chaos 2013, istanbul, turkey •...
TRANSCRIPT
2013 US-Japan JIFT Workshop, Toki-shi
Self-organization and Control in kinetic stimulated Raman backcattering
Miloš M. ŠKORIĆ1, Ljubomir NIKOLIĆ2, Seiji ISHIGURO1 and Kunioki MIMA3
1) National Institute for Fusion Science,
Graduate University for Advanced Studies, Toki, Japan 2) NRCan, Ottawa, ON, K1A 0Y3, Canada
3) Institute of Laser Engineering, Osaka University, Japan
Chaos 2013, Istanbul, Turkey
Motivation
• Laser plasma interactions are a useful test-bed for exploring many nonlinear and complex plasma phenomena, such as resonant 3-wave parametric instabilities, a stimulated Raman scattering, in particular
• In laser fusion concern is due to Backward SRS for energy and symmetry loss and target preheat. Large NIF target backscatter with bursts & broad spectra, hard to model in pF3D code for LPI
• Toward Exawatt intensity regimes, relevant for nuclear and high-energy physics a new method based on Backward SRS (BRS) amplification was proposed. Experiments and PIC simulation show large BRS sensitivity and a narrow operation operational window
2013 US-Japan JIFT Workshop, Toki-shi
(Hinkel, 2011)
Raman complexity - intermittent bursts & spectral broadening
2013 US-Japan JIFT Workshop, Toki-shi
Raman complexity - intermittent bursts & spectral broadening
(Hinkel, 2011)
(Yin, 2012 VPIC, LANL)
R
Chaos 2013, Istanbul, Turkey
• Motivation
• Standard 3WI fluid model & absolute instability conditions
• EPW nonlinear frequency shift => Intermittency & broad spectra
• “Break-up” of Manley-Rowe invariants => Onset of nonstationarity
• Kinetic Raman saturation and Hybrid model (toy)
• FS coherent pulse generation by backward Raman in thin foils
• Future work
Outline
stimulated Raman scattering (SRS)
Langmuir Decay Instability (LDI)
Parametric Decay Instability (PDI)
stimulated Brillouin scattering (SBS)
Two-plasmon Decay (TPD)
laser EPW
EMW
laser
EMW
IAW
laser
EPW
EPW
laser
IAW
EPW
EPW
EPW IAW
Important parametric 3WI in Laser Plasma Instabilities (LPI)
after D. Montgomery (LANL) PRL2002
Stimulated Raman Scattering (SRS) The stimulated Raman scattering is a parametric decay of an incident EM wave into a scattered light and an electron plasma (EPW- Langmuir) wave. The matching condition for the frequencies and wave numbers are
SBS
SBS IAW
Analogous process to SRS, however, involving EMW scattering on an ion acoustic wave (IAW) : stimulated Brillouin scattering (SBS) instability
SRS matching condition
Laser fusion at NIF
Reflectivity vs linear gain=> anomalous!
LLNL, USA
C3 - Cascaded Conversion Compression novel scheme for Exawatt to Zettawat, FS pulse generation ! ?
Mourou, Fisch & Tajima, 2012
(Backward Raman Amplification)
NIF & LMJ !
Evolution of high-power laser systems • 1960: Discovery of laser • 1960-1965: "Q-switched" & "mode-locked" lasers, intensity ~ 1012 W/cm2
• 1965-1985: Increase in laser intensity ~ 1015 W/cm2
• 1985: Discovery of CPA laser • 1985- : quest toward (Ultra-) Relativistic intensities ~ 1018- 1024 W/cm2
][ λ][W/cmI~/c)(v 21/218 µ⊥
"a solution looking for a problem“
][ ][W/cmI~/c)(v 21/218 µλosc
C3 - Cascaded Conversion Compression novel scheme for Exawatt to Zettawat, FS pulse generation ! ?
Mourou, Fisch & Tajima, 2012
(Backward Raman Amplification)
Original proposal of BRA compression of ultra relativistic laser ( 2 stage) failed in 2D PIC, due to “competitive instabilities” , (Fisch & Malkin, 2000- )
2nd stage ?
Saturation of Stimulated Raman Backscattering
Laser pump strength Relativistic NL freq. shift Skoric, et al. PRE1996
nonlinear EPW ?
Nonlinear Stimulated Raman Backscattering
Laser pump strength nonlinear freq. shift e.g. Rosenbluth et al. , 1971
Nonlinear EPW shift due to e.g. electron trapping/LDI/ relativistic
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al. LIRPP1993; PRE1996
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
EPW Intermittency
Fixed point steady state
laser
L -Under-dense Plasma layer control parameter
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al PRE1996, details in Kono & Skoric, Springer (2010) Ch12
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram
Fixed point
Periodic
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al. LIRPP1993; PRE1996
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram
Quasi- Periodic
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al. LIRPP1993; PRE1996
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram
Intermittency
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al. LIRPP1993; PRE1996
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram
Chaos
Pulsations and Route to Chaos in B-SRS see, Skoric et al. LIRPP1993; PRE1996 (Sakagami & Mima, 1990)
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram EPW ST-Intermittency
Fixed point
Periodic
Q-Periodic
Intermittent
Chaos
Bifurcations to low-dimensional Chaos in B-SRS
see, Skoric et al. LIRPP1993; PRE1996
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
EPW Intermittency
Fixed point steady state
laser
L -Under-dense Plasma layer control parameter
Manly-Rowe relations
Manly-Rowe “breaks” => Nonstationary relativistic SRS
(1997)
e.g. Forslund, PF 1975
Skoric AIP, 1997, 2009
Manly-Rowe relations
Manly-Rowe “breaks” => Nonstationary BRS saturation
(1997)
Generic cause for intermittent bursts and spectral broadening in BRS saturation, and poor scaling in Raman amplification!?
e.g., Malkin & Fisch, PoP 2000-2006; see R. Trines et al. PRL & Nature Phys. 2011
e.g. Forslund, PF 1975
Skoric,1996 , details in Book ,Ch12 Kono & Skoric, Springer (2010)
Complexity and Route to Chaos in B-SRS see, Skoric et al. LIRPP1993; PRE1996 (Sakagami & Mima, 1990)
By varying the control (laser& plasma) parameters, Route to chaos in space-time in 3WI relativistic B-SRS is found : via steady-state, periodic, quasi-periodic and intermittent transition to chaos. Complexities in non-stationary bwd- Raman regimes include, strong spiky- burst like temporal Reflectivity & broadened blue-shifted incoherent spectra.
Reflectivity, power spectrum & phase diagram EPW ST-Intermittency
Fixed point
Periodic
Q-Periodic
Intermittent
Chaos
-> absolute BRS
The Great Wave off Kanazawa 神奈川沖浪裏
by K. Hokusai (1832, Edo)
Quantitative Signature of Spatio-Temporal of Raman Complexity
The Topological dimension calculated by the Singular Value Decomposition-SVD
Open convective spatially-extended weakly-confined dissipative model=> Quasi-periodic route to Intermittency
ST- Intermittency in plasma waves
Chaos 2013, Istanbul, Turkey
Control of stimulated Raman backscattering by EPW damping (La)
Chaos 2013, Istanbul, Turkey
Control of stimulated Raman backscatter -Bifurcation diagram for onset of Complexity-
Useful for parametric survey of plasma conditions for BRS
Pulsations and bursts in kinetic stimulated Raman Backscattering (PIC)
Miyamoto, Skoric, Mima, 1998
2013 US-Japan JIFT Workshop, Toki-shi LOKI, LLNL !?
Control of stimulated Raman Backscattering Complexity
• Absolute instability condition is satisfied in uniform plasma, driving a large BRS signal from a background noise. e.g., for moderate pump, I ~ 1014 W/cm2, over ~ 10 microns in 10% Ncr ; absolute Raman dominates • It sets for interaction length- L0 shorter than, both, plasma-L and absorption length-La; L0= (VeVs)1/2/γ0 La=Ve /νe ; γ0 -growth rate, Ve and Vs, group velocity • L0 and La very in time with plasma parameters; hot
electrons, bulk temperature-growth suppress Raman!
2013 US-Japan JIFT Workshop, Toki-shi
Kinetic-hybrid dissipative (toy) model of stimulated Raman Backscattering
γ − effective “kinetic” dissipation (hot electrons/ trapping)
Skoric, PRE1999; Kono & Skoric, Springer (2010) Sect 12.3
2013 US-Japan JIFT Workshop, Toki-shi
Open boundary hybrid model
Skoric, PRE1999
2013 US-Japan JIFT Workshop, Toki-shi
Hot electron balance
2013 US-Japan JIFT Workshop, Toki-shi
Thermal bulk energy balance
Energy balance
2013 US-Japan JIFT Workshop, Toki-shi
Self-organization at Micro & Macro scales versus k- transport coefficient (inhibition)
β0=0.025 , n=0.1ncr, L=100 c/ω0 , Te=0.5 KeV
Closed system (exploding foil)
2013 US-Japan JIFT Workshop, Toki-shi
Self-organization at Micro & Macro scales versus k- transport coefficient (inhibition)
β0=0.025 , n=0.1ncr, L=100 c/ω0 , Te=0.5 KeV
Closed system (exploding foil)
Open system
(large plasma)
2013 US-Japan JIFT Workshop, Toki-shi
Self-organization at Micro & Macro scales versus k- transport coefficient (inhibition)
β0=0.025 , n=0.1ncr, L=100 c/ω0 , Te=0.5 KeV
Closed system (exploding foil)
Open system
(large plasma)
Coherent pulsations
2013 US-Japan JIFT Workshop, Toki-shi
Kinetic-micro scale self-organization
Electron distribution function
2013 US-Japan JIFT Workshop, Toki-shi
PIC versus Hybrid results Closed- exploding foil plasma
Hybrid
FS Pulse Generation by Backward Raman Compression in a Thin Foil Plasma
Skoric,Mima et al. LIRPP(AIP), 1997
3WI coupled model QP Pulsation regime !
Laser L -Under-dense Thin Plasma foil
FS Pulse Generation by Backward Raman Compression in a Thin Foil Plasma (2)
Skoric,Mima et al. LIRPP(AIP), 1997
Green light pulse T0 ~ 1 fs
FS Pulse Generation by Backward Raman Compression in a Thin Foil Plasma (3)
Skoric,Mima et al. LIRPP(AIP), 1997
Green light pulse T0 ~ 1 fs
Pulsations suppressed by hot / bulk electron heating
Particle simulations Single compresed pulse !
Raman compression to FS pulses in a exploding foil plasma- PIC code
Single tailored pulse < 50 fs
Skoric & Nikolic JPP 2013
Raman compression to FS pulses in thin exploding foil plasma- PIC code
Single pulse < 10 fs
Raman compression to FS pulses in a exploding foil plasma- 1D PIC
NO single pulse- Incoherent BRS
Future work on Control of Raman complexity
• By relativistic 1D PIC simulations test feasibility and scaling of FS pulse compression by BRS in thin foils (~ 1 micron), against 3WI model
• By relativistic 2D PIC test the robustness of BRS compression in competition with parametric inst.: forward & side SRS, self-focusing ..
• Parametric study by hybrid BRS model, conditions for suppression of Raman complexity in fusion targets (“Raman map”)
Thank you …!
Plasma and Fusion Science -PhD course National Institute for Fusion Science
Toki, Japan
http://soken.nifs.ac.jp/index.html